Installation guide

On DIGITAL UNIX systems, the two members of the rlimit structure,
rlim_cur and rlim_max are defined as unsigned long instead of as int
on ULTRIX systems. You must modify your application if it depends on this
structure. Otherwise, the getrlimit and setrlimit calls will fail
because of a register sign extension.
B.13 Changes in the stddef.h File
On ULTRIX systems, the wchar_t variable that is defined in stddef.h is
declared to be an unsigned integer (32 bits). On DIGITAL UNIX systems,
the variable is declared to be an unsigned short integer (16 bits).
On ULTRIX systems, the size_t variable that is defined in stddef.h is
declared to be an unsigned integer (32 bits). On DIGITAL UNIX systems,
the variable is declared to be an unsigned long integer (64 bits).
B.14 Changes in the stdio.h File
The stdlib.h header file defines constants and functions I/O services. The
following constant values have been changed in the DIGITAL UNIX
stdio.h file:
Constant ULTRIX Value DIGITAL UNIX Value
BUFSIZ
1024 8192
FILENAME_MAX
1024 255
TMP_MAX
17,576 16,384
B.15 Changes in the stdlib.h File
The stdlib.h header file defines constants and functions for ANSI
compatibility. Two constants are defined to a different value on DIGITAL
UNIX and ULTRIX systems. On DIGITAL UNIX systems, the RAND_MAX
value is defined as 2,147483,647. On ULTRIX systems, this constant is
defined to be 32,767. On DIGITAL UNIX systems, MB_CUR_MAX is
defined as the function _ _getmbcurmax(). This function returns the
maximum number of bytes allowed in a multibyte character in the current
locale. That number is 1 for all the DIGITAL UNIX locales. On ULTRIX
systems, MB_CUR_MAX is defined as 4.
B.16 Changes in the syslog.h File
The syslog.h header file defines constants that are used in the system
log. This header file also defines the routines that control the system log.
B–6 Differences in ULTRIX and DIGITAL UNIX Header Files and Library Routines